1260 DAYS
For 1260 Days or 42 months the two witnesses prophesy in the city of their God.
Remember Days are also used elsewhere in the Bible (cf Daniel) to symbolize years.
Background Reading:
Revelation 11:3-6
The Two Witnesses - 1260 Days
3 And I will give power to my two witnesses, and they will prophesy for 1,260 days, clothed in sackcloth." 4 These are the two olive trees and the two lampstands that stand before the Lord of the earth. 5 If anyone tries to harm them, fire comes from their mouths and devours their enemies. This is how anyone who wants to harm them must die. 6 These men have power to shut up the sky so that it will not rain during the time they are prophesying; and they have power to turn the waters into blood and to strike the earth with every kind of plague as often as they want.